Converting formula from Crystal Reports to SSRS - sql

Question

I'll try and keep this as short as possible but I'm trying to convert a formula cell from crystal report to SSRS.
Here is the query:
SELECT
(SELECT START_DATE
FROM APPS.GL_PERIODS
WHERE PERIOD_TYPE = 'Month'
AND TRUNC(SYSDATE-:Days) BETWEEN START_DATE AND END_DATE) STR_DATE,
(SELECT END_DATE
FROM APPS.GL_PERIODS
WHERE PERIOD_TYPE = 'Month'
AND TRUNC(SYSDATE-:Days) BETWEEN START_DATE AND END_DATE) END_DATE,
DECODE(RT.ORGANIZATION_ID, 104, 'LPD',RT.ORGANIZATION_ID) ORG,
SUBSTR(POV.VENDOR_NAME, 1, 24) VENDOR_NAME,
DECODE(SUBSTR(PHA.SEGMENT1, 2,1), 'E', 'EXPENSE', 'e', 'EXPENSE', 'P', 'PRODUCT', 'p', 'PRODUCT', ' OTHER') PO_TYPE,
DECODE(SIGN(TRUNC(RT.TRANSACTION_DATE) - TRUNC(NVL(PLL.PROMISED_DATE - 3, PLL.NEED_BY_DATE - 3))), -1, 'LATE', 'ON TIME') PERFORMANCE,
COUNT(*) LINE_COUNT
FROM
APPS.RCV_TRANSACTIONS RT,
APPS.PO_HEADERS_ALL PHA,
APPS.PO_LINES_ALL PLA,
APPS.PO_LINE_LOCATIONS_ALL PLL,
APPS.PO_VENDORS POV
WHERE
RT.ORGANIZATION_ID = 104
AND RT.TRANSACTION_DATE >= (SELECT START_DATE
FROM APPS.GL_PERIODS
WHERE PERIOD_TYPE = 'Month'
AND TRUNC(SYSDATE-:Days) BETWEEN START_DATE AND END_DATE)
AND RT.TRANSACTION_DATE < (SELECT END_DATE + 1
FROM APPS.GL_PERIODS
WHERE PERIOD_TYPE = 'Month'
AND TRUNC(SYSDATE-:Days) BETWEEN START_DATE AND END_DATE)
AND RT.TRANSACTION_TYPE = 'RECEIVE'
AND RT.PO_HEADER_ID = PLL.PO_HEADER_ID
AND RT.PO_LINE_LOCATION_ID = PLL.LINE_LOCATION_ID
AND RT.PO_LINE_ID = PLL.PO_LINE_ID
AND RT.ORGANIZATION_ID = PLL.SHIP_TO_ORGANIZATION_ID
AND PLA.PO_LINE_ID = PLL.PO_LINE_ID
AND PLA.PO_HEADER_ID = PLL.PO_HEADER_ID
AND PHA.PO_HEADER_ID = PLA.PO_HEADER_ID
AND PHA.VENDOR_ID = POV.VENDOR_ID
GROUP BY
DECODE(RT.ORGANIZATION_ID, 104, 'LPD', RT.ORGANIZATION_ID),
SUBSTR(POV.VENDOR_NAME, 1, 24),
DECODE(SUBSTR(PHA.SEGMENT1, 2, 1), 'E', 'EXPENSE', 'e', 'EXPENSE', 'P', 'PRODUCT', 'p', 'PRODUCT', ' OTHER'),
DECODE(SIGN(TRUNC(RT.TRANSACTION_DATE) - TRUNC(NVL(PLL.PROMISED_DATE - 3, PLL.NEED_BY_DATE - 3))), -1, 'LATE', 'ON TIME')
ORDER BY
ORG, VENDOR_NAME, PO_TYPE, PERFORMANCE
In crystal the formula is
SUM({query.LINE_COUNT},{query.PERFORMANCE}) % SUM({query.LINE_COUNT}, {query.PO_TYPE})
This cell basically is just calculating the percentage of on time deliveries and late ones.